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Investigative Techniques
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FEATURE - HANDWRITING VERIFICATION


CLICK ON the handwriting to see how an expert could verify that this note is authentic, and written by Ulysses S. Grant.
Letter Strokes

The way someone dots the 'i' and crosses the 't' (diacritic strokes) are a focal point of handwriting comparison. Other indicators are the direction of stroke and shape of loops.

Pen and Ink

Infrared light and chemical tests can prove that more than one ink was used. More than one pen can be confirmed by looking at microscopic marks in the ink.

The Signature

People have three signatures: formal on important papers, routine on paperwork, and informal on notes. If a signature doesn't suit the document, it may be a tracing.

Positioning

In a handwriting comparison, the examiner looks for discrepancies in the vertical positioning of letters, space between lines, or a slant variance of five ° or more.